Device for loading explosives in wells



Dec. 26, 1944. w. P. BLAIR ET A1. 2,365,798

DEVICE FOR LOADING EXPLOSIVES IN WELLS Filed Dec. 2o, 1940 2 sheets-smet1 Dec. 26, 1944. W p. B| A|R ET AL 2,365,798

DEVICE FOR LOADING EXPLOSIVES IN WELLS Filed Dec. 2O 1940 2 Sheets-Sheet2 /M w, M Zu r n ffm m Si I\ ./...1 V N m5. f m W5 Ww lf. .m A w w ff.www, au, A, M y, W W @y @d i a w 7 0 f6 M/ i @Hm w w.. y n0,/ T L, c --1l :y l .n.mwmmm @atented ec. 26, i944 rares DEVICE FOR LADDIG EHLSIVESIN WELLS Oklahoma Application December 20, 1940, Serial No. 370,974

(Cl. ll66 19) 14 Claims.

This invention relates to devices for loading explosives into wells,such as oil, gas and water wells, and particularly to such devices i thetype commonly known to the art as dump shells.

In employing dump shells for loading explosives into wells, theexplosive, which is ordinarily a gelatinized form of nitroglycerine, isplaced in a. suitable container, provided with a bail to .which thelowering line is attached and with a bottom dump valve or releasableplug. rIhis container is lowered into the well, and when. it reaches thebottom at the point where the explosive is to be placed, the dump valveis opened Iby suitable release mechanism ordinarily operated from thelowering line. The gelatinous mass of explosive is then discharged fromthe container into the well. Generally, a plurality of charges ofexplosive are thus deposited in the well by means of the same containeruntil the space within which the explosion is to occur is closely packedwith the explosive material.

It is particularly desirable in employing dump shells in the mannerdescribed that complete dumping of each charge of explosive from theshell be assured so thatnone of the explosive will be carried back tothe surface with the container when it is withdrawn from the well forrecharging. It is also particularly desirable that as little solid,non-explosive matter as possible be deposited in the well during theloading operation, and that metal-to-metal contacts which may producesparks be avoided to reduce the hazard of premature explosions.

The present invention is directed to dump shells of this generalcharacter, and more specifically to improvements in the valve or plug,and the mechanism for releasing it. In the present invention I provide avalve or plug which is separated from the casing when released. Thiseliminates-any possibility `that the valve will be unintentionallyclosed after it has .been opened, and thus assures a complete dischargeof the explosive from the shell.

In accordance with this invention, the desirable objects and advantagesabove-enumerated, as well as others, are attained Iby means of animproved form of dump shell, several modications of which areillustrated in the acompanying drawings and are described in detail inthe following specication. In the drawings:

Fig. l is a longitudinal, partly-sectional view of a dump shell inaccordance with one modification of this invention;

Figs. 2, 3 and 4 are views similar to Fig. i illustrating diierentpositions of the release mechanism of the shell during the course of thedumping operation;

Fig. 5 is a side elevationof the upper end of the shell, at right anglesto Fig. l;

Fig. 6 is a longitudinal elevation of a durnp shell in accordancewithanother modification of this invention, parts being shown insection;

Fig. 7 is a horizontal, sectional view on line 'll of Fig. 6;

Figs. 8 and 9 are details of one form of closure adapted for use withthe modification of Fig. 6;

Fig. l0 is a vertical, sectional view of the lower end of the shell ofFig. 6, showing another form of valve; and

Fig. 11 is a plan view of the valve shown in. Fig. 10.

Referring to Figs. l to 5 of the drawings, the device consists of anelongated hollow tubular casing 2li constructed preferably of lightsheet metal, such as tin plate or the like, which is open at both end.Secured to the upper end of casing 2D is an elongated U-shaped bail 2l,having the lower ends of its arms securely attached at opposite sides tothe upper end of casing 20. A spacer bar 22 extends transversely betweenthe arms of bail 2l at a point intermediate the open upper end ofcasingl 2l] and the bow portion of bail 2l. Spacer bar 22 and the lbowportion of bail 2l, respectively, are provided with registering openings23 and 24 in alignment with the longitudinal axis of casing 20. Atubular sleeve v25 extends between spacer -bar 22 and the bow portion ofIbail 2l and encloses `both the openings 23 and 2d. A tubular stem 26extends from above bail 2| through openings 23 and 24 and sleeve 25 tobelow spacer bar 22. Stern 26 is adapted to slide longitudinally throughthe sleeve 25 and the openings 23 and 2li. A ring 2l is attached to theupper end of stem 26 for attachment of a lowering line 28. Stem 26 isprovided in an intermediate lportion thereof with a transverse slot 29.A dog 3U is positioned in the slot and eccentrically journalled in thesides of stem 26. A key slot 3| extends through stern 26 at a pointabove slot 29 and is adapted to receive a wedgeshaped key 32. A bushing33 is threadeclly inserted into the lower end oi .stem 26 and isprovided with an axial opening 34 through which the upper end of a rod35 extends into the bore of stem 26. The upper end of rod 35 is providedwith a cap 36 which cooperates with the inner end of bushing 33 toprevent downward withdrawal of the end of -rod 35 from the bore of stem26. The described arrangement of rod 35 in stem 26 permits relativetelescoping movement between these parts, as shown 'by the extendeddotted outlines of stern 25 in Fig. l. Rod 35 extends axially of fromthe lower end of rod 35.

provided with an upper shank portion 39 which is adapted to be insertedinto the lower end of casing 20 to form a closure therefor. Shank 39terminates at an annular shoulder 40 which engages the lower end ofcasing 20 and thereby limits the extent of insertion of the plug intothe casing. The lower portion of plug 38 below shoulder 40 forms anextended tip of generally conical shape, although the shape of this tipis largely immaterial. It may be round or 'at or of any other suitableconfiguration. The shank portion 39 is provided in each itshalf-sections with complementary grooves 4| which terminate in theinterior of the plug in a conical recess 42.

When the half-sections of plug 38 are closed about the lower end of rod35, tip 31 will be received in recess 42 and the adjacent portion of rod35 will be received in groove 4|. When the shank of plug 38 is insertedin the lower end of casing by drawing rod 35 upwardly through thecasing, the plug will be held in place in the end of the casing by thewedging action of tip 31 against the adjacent faces of recess 42 and bythe cooperation of shoulder4|l with the lower edge of casing 20. Ears 43(see Fig. 5) may be attached at opposite sides of the upper portion ofbail 2| for attachment of the usual well rig hoisting line whenever itis desired to lift the shell from the well rig floor or from some otherplace before attachment of lowering line 28, Iin order to avoid placingan undesirable bending strain on stern 26. A chain 44 or other flexibletie means connects key 32 to one of the ears 43 to prevent loss of thekey when not used for locking stem 26 in its fully extended position.

The operation of the above-described dump shell is as follows: Thehalf-sections of closure plug 38 are placed about the lower end of rod35 and tip 31 and shank 39 is inserted in the lower end of casing 26,stem 26 being drawn upwardly to the fully elevated position illustratedparticularly in Figs. 1 and 2. Key 32 is inserted in slot 3| and theentire device suspended vertically from lowering line 28. When the shellis thus suspended from the lowering line, the weight of the shell on theshoulder 40 will holdthe plug in place in the end of the casing, and thekey 32 is not necessary for any purpose except as a precautionarymeasure in the event some unexpected upward movement is applied to theshell. It is useful, however, to keep the plug 38 in place and the partsin their assembled relationship when the shell is not in suspendedposition. Casing 2U is now lled with the explosive material, which asstated above, is usually of a gelatinous or jelly-like composition whichwill ordinarily slide from the lower end of the casing when the plug isremoved. This sliding vof the explosive from the container is usuallyaided by coating the interior of the casing with a suitable lubricant.It will be seen that the weight of the shell and explosive will besupported on the tapered surface of tip 31 which cooperates with theadjacent tapered surfaces of recess 42 to cause an expanding movement ofthe half-sections of plug 38 into tight engagement with the walls ofcasing 20. Thus, so long as the weight of the shell and contents iscarried by stem 26 and rod 35 closure plug 38 will be held in place inthe end of" the shell casing.

Key 32 is now withdrawn from slot 3| and the loaded shell is loweredinto the well. When the tip of closure 38 strikes the bottom of thewell, the downward progress of casing 29, bail 2| and rod 35 arearrested but stem 26 is free to continue its downward movement, bytelescoping over rod 35, until its downward movement is arrested bycontact of ring 21 with the `bow portion of bail 2|. The resultantposition of stem 26 is shown by the dotted outlines in Fig. 1, and morecompletely in Fig. 3. This continued downward movement of stem 26 bringsslot 29 and dog 30 out of sleeve 25 and below spacer plate 22, whereupondog 39, being normally unbalanced by its eccentric journalling in slot29, rotates to the position shown in Figs. 3 and 4. An upward pull isthen applied to line 28 which pulls stem26 upwardly toward its normalposition until dog 38 comes in contact with the under side of spacerplate 22 (Fig. 4), whereupon the upward pull on line 28 becomes appliedto casing 20. At the same time, contact of dog 30 with spacer plate 22prevents return of bushing 33 into contact with cap 36 on the upper endof rod 35 with the result that some relative movement between the upperend of rod -35 and bushing 36 can occur after dog 30 contacts spacerplate 22 upon continued upward movement of line 28. The extent of thisrelative movement is suilicient to allow casing 2D to be pulled off ofshank 39 of closure 38 which is held the weight of the explosive bearingon the top of the plug. As soon as plug 38 is freed from confinementwithin the end of the casing, the half-sections of the plug separate andare thrust away from tip 31 by the weight of the explosive and thewedging action of tip 31 against the sides of recess 42. The explosivematerial is then discharged from the end of the casing, sliding out ofits own weight, and deposits in the well. The entire shell with theexception of closure plug 38, is then withdrawn from the well. A. newclosure plug is then inserted in the end of the casing in the mannerdescribed and the shell loading and dumping operations repeated until asuicient charge of explosive has been discharged into the well.

By employment of a dump shell of the abovedescribed construction, havinga fully releasable plug, positive and full opening of the lower end ofthe shell is assured, so ythat complete discharge of the containedexplosive will take place without danger that any explosive will remainin the shell when it is withdrawn from the well. By leaving only theclosure plug in the well, a minimum amount of non-explosive solid matterwill thus remain in the well to interfere with subsequent clean-outoperations.

Since closure plug 38 serves only as a temporary closure and isdiscarded with each use, it may be made of any cheap and convenientmaterial, metallic or non-metallic, which is, however, non-sparking incharacter, Plug 38 may be made of non-sparking metals such as aluminumor copper, or of various non-sparking metal alloys. It may also beconstructed of many non-metallic materials such as glass, wood, resinousplastics, compressed' paper or the like. It is preferable, however, toemploy a material which may be easily shattered by the explosion orwhich may be easily ground up by the tools employed in cleaning out thewell following detonation of the explosive.

Figs. 6 to 9 illustrate another modification of a dump shell inaccordance with this invention having a slightly modied form of closureplug and release mechanism therefor. In this modification the centralrod 35 of Fig. l is replaced by a pair of rods 58-50 which are slidableexternally on opposite sides of casing 20 and are attached at theirupper ends to the opposite ends of a transverse yoke Yoke 5I is slidableexternally of stem 26 betweenf'spacer plate 22 and a stop member 52attached to the lower end of stem 26. The lower ends of rods 50-50 areturned inwardly toward the axis of the shell to form lugs 54-54 whichengage in complementary recesses 53 formed in the outer surfaces of thehalf-sections of plug 38a and on opposite sides thereof below shoulder40. An annular ring 55 encircles the lower end of casing20 and isprovided `at opposite sides with openings 56-56 through which the lowerends of rod Sil-50 are slidably guided to prevent spreading of the endsof rods 50-50 under the weight of the explosive on 'top of the closureplug.

This modification is operated by exactly the same mechanical movementsof stem 26 and dog 3!) as the previously described modification, toeiect release of closure plug 38a and to discharge the explosive.

Figs. and l1 illustrate details of another variation of the modificationillustrated in Fig. 8,

able plug mounted in the lower end of the casing and serving as aclosure therefor, plug retaining means comprising a lower memberextending longitudinally of the casing, engaging the plug to retain itin position and being separable therefrom, and an upper retaining memberconnected to the lower retaining member, the retaining members beingcapable of limited longitudinal contractura] and extending movement, theupper end of the' upper retaining memberl beingadapted to be secured toa lowering line, the plug 'retaining means being suspended in extendedrelation by the lowering line, /and means operative upon predeterminedlongitudinal contractural movement between the upper and lower retainingmembers to lock the upper retaining member against movement with respectto the casing whereby upward movement of the upper retaining member andthe casing causes the lower retaining member and the plug to moverelatively to the casing to release the plug.

2. In a device of the character described, a casing having an outletopening in the bottom, a separable plug received in the opening, plugretaining means extending through the casing and adapted to` be securedto a lowering line whereby upward pull is placed on the plug retainingmeans to hold the plug in position during lowering into a well, the plugretaining means comprising a lower member engaging the plug and an uppermember connected to the lower member, the upper and lower retainingmembers being relatively movable to permit limiting longitudinalcontractural and extending movement of the retaining means, and meanscarried by the upper retaining member and engageable with a part of thecasing when the retaining means is contracted to lock the upperretaining member against relative movement with respect to the casing.

3. In a device of the character described, a cylindrical casing havingan open lower end, a releasable plug closing the lower end of thecasing, the plug having a shoulder engaging the lower end of the casing,plug retaining means comprising a lower member extending longitudinallyof the casing and engaging the plug and an upper retaining memberconnected to the lower retaining member to permit relative longitudinalmovement of said members with respect to each other and with respect tothe casing, the retaining means being capable of longitudinal limitedcontractural and extending movement, the upper end of the upperretaining member being adapted to be secured to a lowering line, and adog carried by the upper retaining member engageable with a part of thecasing when the retaining member is contracted to lock the upperretaining member to the casing.

4. A dump shell for vlowering explosives into a well comprising a casinghaving a discharge opening in the bottom thereof, a fully separable plugclosing said opening, and means for retaining the plug in position, saidmeans comprising a lower retaining member engaging the plug and an upperretaining member extending above the top of the shell` for attachment toa lowering line, the

retaining members being connected to each other to permit relativemovement and being movable with respectto the casing, the retainingmeans being capable of limiting longitudinal contractural and extendingmovement, and means for locking the upper retaining member to the casingwhen the retaining means is contracted to permit relative downwardmovement of the lower retaining member and release of the plug.

5. A device of the character described comprising a substantiallycylindrical casing, a fully releasable plug mounted in the lower end ofthe casing, plug retaining means extending longitudinally of the casing,the .plug retaining means comprising an upper member and a lower memberconnected to each other to permit relative movement to'elect limitinglongitudinal contractura] and extending movement, a sleeve carried onthe casing, the upper retaining member being mounted in the sleeve, theupper end of the upper retaining member being adapted to be secured to alowering line, and means carried by the upper retaining member to engagea portion of the casing when the retaining means is contracted to lockthe upper retaining member against movement with respect to the casing.

6. In a device of the character described, a substantially cylindricalcasing, a fully releasable plug mounted in the lower end of the casing,plug retaining means comprising a lower member extending longitudinallyof the casing and engaging the plug and an upper member mounted in thecasing, the upper member being loosely connected to the lower member,the plug retaining means being capable of limiting longitudinalcontractural and extending movement, the upper retaining member beingadapted to be secured to a lowering line, the plug retaining means beingsuspended in expanded relation by the lowering line, and means carriedby/the upper retaining member and adapted to engage a portion of thecasing when the retaining means is contracted to lock the casingrandupper retaining member against relative movement.

'7. In a device of the character described a substantially cylindricalcasing, a fully releasable plug mounted in the lower end of the casing,plug retaining means comprising a lower member extending longitudinallyof the casing and engaging the plug and an upper member mounted in thecasing, the upper member being connected to the lower member to permitlimited relative movement, the retaining means being capable of limitinglongitudinal contractural and extending movement, the upper member beingadapted to be secured to a lowering line, the plug retaining means beingsuspended in extended relation by the lowering line, and a dog carriedby the upper member and adapted to engage a portion of the casing whenthe retaining means is contracted to lock the upper member and casingagainst relative longitudinal movement.

8. In a device of the character described, a. substantially cylindricalcasing, a fully releasable plug mounted in the lower end of the casing,plug retaining means comprising a lower member extending longitudinallyof the casing and an upper member connected to the lower member topermit limited relative longitudinal movement of said members, the plugretaining means being capable of limiting longitudinal contractural andextending movement, a sleeve carried on the upper end of the casing, aspacer bar arranged adjacent the lower end of the sleeve, the upper endof the upper retaining member being adapted to be secured to a loweringline, the plug retaining means being suspended in extended relation bythe lowering line, and means carried by the upper member and engagingthe spacer bar when the retaining means is contracted'to lock the upperretaining member and casing againstl relative movement.

9. In a device of the character described, a substantially cylindricalcasing, a fully releasable plug mounted in the lower end of the casing,the plug being for-med in two sections, plug retaining means comprisinga lower member extending longitudinally of the casing and engaging thesections of the plug, and an upper retaining member connected to thelower retaining member to permit limited longitudinal movement oi saidmembers, the .plug retaining means being capable of movement withrespect to the casing, the upper retaining member being adapted to besecured to a lowering line, the plug retaining means being suspended inextended relation by the lowering line, and means carried by the uppermember and engaging a portion of the casing when the retaining means iscontracted to lock the upper member against relative movement withrespect to the casing.

l0. In a device of the character described, a substantially cylindricalcasing, a fullyreleasable plug mounted in the lower end of the casing,said plug retaining means comprising a rod extending axially of thecasing7 and a second member telescopically connected thereto to permitlimiting relative longitudinal movement of said members with respect toeach other and with respect to the casing, the second member beingadapted to be Secured to a lowering line, the plug retaining means being'suspended in extended relation by the lowering line, and means carriedby the second member and engaging a portion or the casing when theretaining means is contracted to lock the second member against relativemovement with respect to the casing.

ll. A device of the character described comprising a substantiallycylindrical casing, a plug niouni id in the lower end of the casing, theplug comp a pair of sections having registering grooves and recesses ontheir adjacent faces, a plug retaining member mounted in the casing,said plug retaining member comprising a rod arranged axially of thecasing and having an enlargement on its lower end, the enlargement beingreceived in the recess-es of the plug with the lower end of the rod inthe grooves to retain the plug in position, and a second member slidablymounted on the casing, said members being connected to each other topermit limiting longitudinal movement with respect to each other andwith respect to the casing, the second member being adapted to besecured to a lowering line, the plug retaining means being suspended inextended relation by the lowering line, and means carried by the secondmember and adapted to engage a portion of the casing when the retainingmeans is contracted to lock the second member against relative movementwith respect to the casing.

l2. In a device of the character described, a

f' substantially cylindrical casing, a plug removably mounted in thelower end of the casing,

plug retaining means mounted on the casing, said' plug retaining meanscomprising a pair of rods arranged exteriorly of the casing having theirlower ends shaped to engage the plug to hold it in place, and a secondmember slidably mounted on the casing, s aid members being connected toeach other to permit limited. longitudinal movement with respect to eachother and with respect to the casing, the second member being adapted tobe secured to a lowering line, the plug retaining means being suspendedin extended relation by the lowering line, and means being carried bythe second member and adapted to engage the casing when the retainingmeans is contracted to lock the second member against relative movementwith respect to the casing.

13. In a device of thecharacter described, a substantially cylindricalcasing, a plug removably mounted in the lower end of the casing, plugretaining means mounted on the casing, said plug retaining meanscomprising a pair of rods arranged exteriorly of the casing having theirlower ends shaped to engage the plug to hold it in place, a sleevemounted on the upper end of the casing, and a second member slidablymounted in the sleeve, said members being connected to each other topermit limited longitudinal relative movement of said members withrespect to each other and with respect to the casing, the second memberbeing adapted to be secured to a lowering line, the plug retaining meansbeing suspended in extended relation by the lowering line, and meanscarried by the second member and engaging a portion of the casing whenthe retainingA means is contracted to lock said second member againstrelative movement with respect to the casing.

14. In a device of the character described, a substantially cylindricalcasing, a plug removably mounted in the lower end of the casing, plugretaining means mounted on the casing, said plug retaining meanscomprising a pair of rods arranged exteriorly of the casing having theirlower ends shaped to engage the plug to hold it in place, a sleevemounted on the upper end of the casing, a spacer bar arranged adiacentthe lower end of the sleeve, and a second member slidably mounted in thesleeve, said members being connected to each other to permit relativelongitudinal movement ci said members with respect to each other andwith respect to the casing, and a key carried by the second member andadapted to engage the spacer bar when the retaining means is contractedtc lock the second member against; relative movement with respect to thecasing.

WALLACE P. BLAIR. WILLY A. SCHILLINGER.

